There are many instances in which it can be advantageous to thermally insulate an object. Examples include insulation for hot and cold fluid containers and fluid carrying pipes, where the term “fluid” should be interpreted as including liquids, gasses and indeed any composition that flows.
In some instances the object to be insulated is mechanically coupled to one or more members that vibrate and/or move relative to the object or to each other. For example, a blower in a diesel engine is often mechanically coupled between an engine and a vehicle body. The engine has considerable vibration, and moves relative to the vehicle body in at least two degrees of freedom of motion, including rotation and displacement.
In such instances applying a prior art jacket to the object tends to result in loss of functionality and possibly eventual destruction of the jacket. For example, a pipe for recirculation of exhaust gas (EGR pipe) is located between components of the exhaust system and an engine intake and is at least partially exposed to the environment. Because its location, heat losses occur during the transfer of the hot exhaust gas from the exhaust system to the combustion chamber. To reduce unwanted heat transfer, EGR pipes are commonly wrapped with the insulating materials. Such materials can include a thermal blanket with stainless steel springs or wire, a metal, and fiberglass mat. However, during operation of the vehicle, components of the exhaust system and the engine move due to operation of the engine and interactions with rough road surfaces. Under such conditions the engine and components of the exhaust system move relative to each other and to the frame or body of the vehicle, to which such an EGR pipe is typically anchored. Such movements place considerable stress on the insulating materials wrapping the EGR pipe, causing them to be stripped off from the pipe. This can result in the need for can require frequent replacements of these insulating materials.
Insulation devices have been proposed that attempt to compensate for such motion through the use of expandable pipe sections. United States Patent Application No. US 2012/014634 to Keyes, for example, uses a flexible bellows and additional insulating and joining components to provide a watertight encasement for a traditional metal expansion joint. Similarly, U.S. Pat. No. 5,134,846 to White discloses the use of a flexible metal sleeve that holds insulating materials in contact with exhaust system components. Such approaches do accommodate movement between the joined structures, but do so at the cost of compressing the insulating material. Such compression reduces the effectiveness of the insulating material and can result in damage that requires replacement. U.S. Pat. No. 5,092,122 to Bainbridge describes the use of a pair of corrugated metal tubes that have a space between them that is filled with insulating material. These can be slid over a pipe to provide insulation, the corrugations allowing for a certain degree of movement. Such a device, however, places the inner corrugated tube in contact with the pipe being insulated, and can abrade the pipe surface as components to which the pipe is connected move.
All publications identified herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
Thus, there is still a need for insulation devices, methods and materials that accommodate significant movement of joined components, or of an insulated component relative to an externally coupled component, without bucking of the insulation.